1. Field of the Invention
This invention is directed to oil compositions for use in electrical discharge machining, also called electrical spark machining.
2. Prior Art
Electrical discharge machining is known as a process for the removal of electrically conductive materials from workpieces by taking advantage of artificial electric sparks. In general, this process is used to form holes of varying shapes in materials of poor machinability and to make cavities in steel dies. It permits accurate machining and thus finds extensive application to not only the formation of molds but also various other sectors of industry.
The above machining process is effected with the use of a cutting fluid disposed in a space between an electrode and a workpiece and serving to generate an electric spark. Certain cutting fluids have been used to this end in which are included kerosines, naphthenic hydrocarbons, n-paraffins, iso-paraffins and the like. However, such known oils have still much to be desired because they involve prolonged machining time and hence reduced production rate.